After delving into these types of parts, I've found that there are a lot of variations in naming conventions and types of parts. The GT2 in the description refers to a teeth pitch of 2mm, the GT refers to a rounded tooth on the belt / pulley. I added an image that shows the difference between teeth type. The teeth on the belt are rounded - from all the research I've done I understand that the rounded teeth help prevent backlash. This kit comes with a set of motor mount, idler, tensioners, clamps etc.. which are all compatible. I'm not sure if I can make use of the tensioner springs, but appreciate its part of the set just in case I can use it.

I have a Tevo Tarantula and these are the same size pulleys and belt that are on my 3D printer. I was able to replace a failing pulley with one of these and it was a perfect fit. I plan to use the rest of them in some other electronics projects on some stepper motors. Nothing bad to say about this kit.

All of the parts are durable and sturdy. The bearings in the idle pulleys are smooth and the belt is strong.

This set is a must have for anyone owning a belted 3D printer! These belts obviously go bad over time and some quicker than others. Stuff happens! It's always good to keep a stock kit like this for your everyday needs, I just replaced a belt on a printer that was only a month old, trust me this stuff happens more than you'd like. Highly recommen

If you're building, fixing, or upgrading an X/Y frame for a 3D printer, this is a good set. It comes with a standard belt and well-machined aluminum geared pulleys. I would not recommend using included torsion springs as they cause the belt to deform. Your belt holding mechanism should take care of torsion instead.

Everything with this is as expected. I have a couple of printers that are past due for belt replacements. I had already added the second Z drive. This was a fairly easy add on. It fits and works.